由于预加载数据库有点大，我想在第一次加载数据库时添加一个旋转轮进度对话框。编码如下：
@Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.exercises_main);
SharedPreferences settings = this.getSharedPreferences("MyApp",0);
boolean firstrun=settings.getBoolean("firstrun_ex",true);
if (firstrun)
{
SharedPreferences.Editor e = settings.edit();
e.putBoolean("firstrun_ex",false);
e.commit();
new performBackgroundTask().execute(); //LINE 71
}
...
private class performBackgroundTask extends AsyncTask<Void, Void, Void>
{
@Override
protected void onPreExecute()
{
dialog= new ProgressDialog(Exercises_MainActivity.this);
dialog.setCancelable(false);
dialog.setMessage("Downloading! Please wait...!");
dialog.show();
}
@Override
protected Void doInBackground(Void... params)
{
initDB(); //LINE 206
return null;
}
protected void onPostExecute(Void result)
{
super.onPostExecute(result);
dialog.dismiss();
}
}
private void initDB() //LINe217
{
if(Ex_dbHlp == null)
Ex_dbHlp = new Keepfit_Ex_DataBaseHelper(this);
Ex_dbHlp.fillDB(); //LINE221
exercises = Ex_dbHlp.get_All_Ex_Data();
}
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.exercises_main);
SharedPreferences settings = this.getSharedPreferences("MyApp",0);
boolean firstrun=settings.getBoolean("firstrun_ex",true);
if (firstrun)
{
SharedPreferences.Editor e = settings.edit();
e.putBoolean("firstrun_ex",false);
e.commit();
initDB();
}
public void fillDB()
{
SQLiteDatabase db = getWritableDatabase();
ContentValues[] values = new ContentValues[63];
for(int i=0; i<values.length; i++)
values[i] = new ContentValues();
values[0].put("id", "001");
values[0].put("ex_group", "group1");
values[0].put("ex_name", "name1");
values[0].put("ex_cal", "cal1");
for(ContentValues row : values)
{
db.insert(TABLE_NAME, null, row);
}
db.close();
}
07-22 01:05:54.370: E/AndroidRuntime(28070): FATAL EXCEPTION: AsyncTask #1
07-22 01:05:54.370: E/AndroidRuntime(28070): java.lang.RuntimeException: An error occured while executing doInBackground()
07-22 01:05:54.370: E/AndroidRuntime(28070): at android.os.AsyncTask$3.done(AsyncTask.java:299)
07-22 01:05:54.370: E/AndroidRuntime(28070): at java.util.concurrent.FutureTask$Sync.innerSetException(FutureTask.java:273)
07-22 01:05:54.370: E/AndroidRuntime(28070): at java.util.concurrent.FutureTask.setException(FutureTask.java:124)
07-22 01:05:54.370: E/AndroidRuntime(28070): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:307)
07-22 01:05:54.370: E/AndroidRuntime(28070): at java.util.concurrent.FutureTask.run(FutureTask.java:137)
07-22 01:05:54.370: E/AndroidRuntime(28070): at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:230)
07-22 01:05:54.370: E/AndroidRuntime(28070): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076)
07-22 01:05:54.370: E/AndroidRuntime(28070): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:569)
07-22 01:05:54.370: E/AndroidRuntime(28070): at java.lang.Thread.run(Thread.java:856)
07-22 01:05:54.370: E/AndroidRuntime(28070): Caused by: java.lang.IllegalStateException: attempt to re-open an already-closed object: SQLiteDatabase: /data/data/com.abc.abc/databases/abc
07-22 01:05:54.370: E/AndroidRuntime(28070): at android.database.sqlite.SQLiteClosable.acquireReference(SQLiteClosable.java:55)
07-22 01:05:54.370: E/AndroidRuntime(28070): at android.database.sqlite.SQLiteDatabase.insertWithOnConflict(SQLiteDatabase.java:1437)
07-22 01:05:54.370: E/AndroidRuntime(28070): at android.database.sqlite.SQLiteDatabase.insert(SQLiteDatabase.java:1339)
07-22 01:05:54.370: E/AndroidRuntime(28070): at com.abc.abc.Abc_Ex_DataBaseHelper.fillDB(Abc_Ex_DataBaseHelper.java:370)
07-22 01:05:54.370: E/AndroidRuntime(28070): at com.abc.abc.Exercises_MainActivity.initDB(Exercises_MainActivity.java:221)
07-22 01:05:54.370: E/AndroidRuntime(28070): at com.abc.abc.Exercises_MainActivity.access$0(Exercises_MainActivity.java:217)
07-22 01:05:54.370: E/AndroidRuntime(28070): at com.abc.abc.Exercises_MainActivity$performBackgroundTask.doInBackground(Exercises_MainActivity.java:206)
07-22 01:05:54.370: E/AndroidRuntime(28070): at com.abc.abc.Exercises_MainActivity$performBackgroundTask.doInBackground(Exercises_MainActivity.java:1)
07-22 01:05:54.370: E/AndroidRuntime(28070): at android.os.AsyncTask$2.call(AsyncTask.java:287)
07-22 01:05:54.370: E/AndroidRuntime(28070): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
07-22 01:05:54.370: E/AndroidRuntime(28070): ... 5 more
07-22 01:06:02.465: I/Choreographer(28070): Skipped 464 frames! The application may be doing too much work on its main thread.
07-22 01:06:03.880: E/WindowManager(28070): Activity com.abc.abc.Exercises_MainActivity has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView@4228c4c0 that was originally added here
07-22 01:06:03.880: E/WindowManager(28070): android.view.WindowLeaked: Activity com.abc.abc.Exercises_MainActivity has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView@4228c4c0 that was originally added here
07-22 01:06:03.880: E/WindowManager(28070): at android.view.ViewRootImpl.<init>(ViewRootImpl.java:403)
07-22 01:06:03.880: E/WindowManager(28070): at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:311)
07-22 01:06:03.880: E/WindowManager(28070): at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:224)
07-22 01:06:03.880: E/WindowManager(28070): at android.view.WindowManagerImpl$CompatModeWrapper.addView(WindowManagerImpl.java:149)
07-22 01:06:03.880: E/WindowManager(28070): at android.view.Window$LocalWindowManager.addView(Window.java:554)
07-22 01:06:03.880: E/WindowManager(28070): at android.app.Dialog.show(Dialog.java:277)
07-22 01:06:03.880: E/WindowManager(28070): at com.abc.abc.Exercises_MainActivity$performBackgroundTask.onPreExecute(Exercises_MainActivity.java:200)
07-22 01:06:03.880: E/WindowManager(28070): at android.os.AsyncTask.executeOnExecutor(AsyncTask.java:586)
07-22 01:06:03.880: E/WindowManager(28070): at android.os.AsyncTask.execute(AsyncTask.java:534)
07-22 01:06:03.880: E/WindowManager(28070): at com.abc.abc.Exercises_MainActivity.onCreate(Exercises_MainActivity.java:71)
07-22 01:06:03.880: E/WindowManager(28070): at android.app.Activity.performCreate(Activity.java:5206)
07-22 01:06:03.880: E/WindowManager(28070): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1094)
07-22 01:06:03.880: E/WindowManager(28070): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2074)
07-22 01:06:03.880: E/WindowManager(28070): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2135)
07-22 01:06:03.880: E/WindowManager(28070): at android.app.ActivityThread.access$700(ActivityThread.java:140)
07-22 01:06:03.880: E/WindowManager(28070): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1237)
07-22 01:06:03.880: E/WindowManager(28070): at android.os.Handler.dispatchMessage(Handler.java:99)
07-22 01:06:03.880: E/WindowManager(28070): at android.os.Looper.loop(Looper.java:137)
07-22 01:06:03.880: E/WindowManager(28070): at android.app.ActivityThread.main(ActivityThread.java:4921)
07-22 01:06:03.880: E/WindowManager(28070): at java.lang.reflect.Method.invokeNative(Native Method)
07-22 01:06:03.880: E/WindowManager(28070): at java.lang.reflect.Method.invoke(Method.java:511)
07-22 01:06:03.880: E/WindowManager(28070): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1027)
07-22 01:06:03.880: E/WindowManager(28070): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:794)
07-22 01:06:03.880: E/WindowManager(28070): at dalvik.system.NativeStart.main(Native Method)
我想在加载数据库时添加一个简单的旋转轮进度对话框...但它失败并报告上面的logcat。
如果我直接删除写initDB（）;在onCreate中，数据库可以正确加载，因此提取所有数据库数据应该没有问题。
如果那么上述问题怎么解决？非常感谢!!